【作者】 毕可然；

【导师】 宋大祥； 周开亚；

【作者基本信息】 南京师范大学 ， 动物学， 2005， 硕士

【摘要】 本研究基于核rDNA与16S rDNA部分序列探讨了隙蛛亚科的分类地位,并对蜘蛛类16S rDNA3′端二级结构进行了研究。 1 核基因与线粒体基因在蜘蛛类系统发生中的应用 核基因与线粒体基因在生物进化过程中不断积累着变异,能够提供物种进化历史的精确信息。本文综述了核基因与线粒体基因在蜘蛛类系统发生中的应用情况。 2 漏斗蛛科与暗蛛科研究概况 漏斗蛛科与暗蛛科是蜘蛛目的两个重要类群。本文简要地介绍了漏斗蛛科与暗蛛科的研究历史、形态特征和生物学特性。 3 从核rDNA序列探讨隙蛛亚科的分类地位 隙蛛亚科Coelotinae原隶属于漏斗蛛科Agelenidae,现已转入暗蛛科Amaurobiidae。关于隙蛛亚科究竟隶属于漏斗蛛科抑或暗蛛科仍存在疑义。我们测定了隙蛛亚科2属、漏斗蛛亚科2属、暗蛛亚科1属和管巢蛛科1属的核28S rDNA和18S rDNA部分序列,选用狒蛛科Theraphosidae为外群,进行系统发生分析。基于28S rDNA和18S rDNA+28S rDNA序列重建的NJ树、MP树、ML树和BI树均支持隙蛛亚科是漏斗蛛亚科的姐妹群,并强烈支持隙蛛亚科+漏斗蛛亚科是暗蛛亚科的姐妹群。基于18S rDNA序列分析所得树的拓扑结构与28S rDNA序列的相似,但置信度偏低。因此,我们认为隙蛛亚科Coelotinae可能是漏斗蛛科Agelenidae的一个亚科。 4 蜘蛛类16S rDNA部分序列高变区二级结构分析及在系统发生重建中的应用更多还原

【Abstract】 This study discusses the classification of the spider subfamily Coelotinae based on the nuclear rDNA and 16S rDNA partial sequences, and studies the secondary structure of the 3’ half of 16S rDNA.1 The application of the nuclear and mitochondrial genes in the spiders’ phylogenetic studyThe nuclear and mitochondrial genes can provide accurate information because they continually accumulate variation in the course of evolution. The application of the nuclear and mitochondrial genes in the phylogenetic studies of spiders is reviewed.2 Review of the studies on families Agelenidae and AmaurobiidaeThe families Agelenidae and Amaurobiidae are two important families in Araneae. This chapter introduces briefly the research history, morphological characteristics, and biology of the two families.3 Phylogenetic position of the spider subfamily Coelotinae (Araneae) inferred from nuclear rDNA sequencesThe phylogenetic position of the subfamily Coelotinae, which belongs to Amaurobiidae currently but Agelenidae formerly, has remained controversial. The sequences of 28S and 18S rDNA fragments from six species of spiders, representing Ageleninae, Amaurobiinae, Coelotinae and Clubionidae, respectively, were obtained.The NJ, MP, ML and BI analyses generated identical topology. All trees from the 28S rDNA and 28S rDNA combined with 18S rDNA data derived from NJ, MP, ML and BI analyses support the Coelotinae as the sister group of the Ageleninae, and strongly support the Coelotinae + Ageleninae are the sister group of the Amaurobiinae. The topology in the trees inferred from 18S data is similar to those of 28S rDNA but with lower boostrap support. The results indicate that Coelotinae is probably a subfamily of the family Agelenidae.4 An analysis of the secondary structure of the hypervariable region of the 16S rDNA in spiders and its implications in phylogenetic reconstructionBased on the model given by Gutell et al. (1996), secondary structures were proposed for the hypervariable region of the 3’ half of the 16S rDNA in the Tamgrinia tibetana (Amaurobiinae) and Asiacoelotes plancyi (Coelotinae), which were also analyzed by combining with the similar structures of four species in the Arachnids (Smith et al. 2003). The analysis revealed a trend of stem and loop reduction in araneae. The maximum parsimony analysis on 16S sequences for which the more variable regions were excluded, revealed that the relationship between Coelotinae and Ageleninae is closer than that between Coelotinae and Amaurobiinae. The result was also supported by the other analysis of the combined 18S^28S and morphological data. This study demonstrates the utility of secondary structure of rDNA in the phylogenetic reconstruction in spiders.更多还原